


Fluid Dynamics

by paintstroke



Category: Voltron: Legendary Defender
Genre: Anal Plug, Anal Sex, Bath Sex, Bubble Bath, M/M, Plot What Plot/Porn Without Plot, Post-Coital Cuddling, Sex Toys, Shameless Smut, Smut, Teasing, Vibrators
Language: English
Status: Completed
Published: 2017-09-03
Updated: 2017-09-03
Packaged: 2018-12-23 11:19:24
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,635
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11988729
Author URL: https://archiveofourown.org/users/paintstroke/pseuds/paintstroke
Summary: (PWP)  It had been easy to agree to. Shiro had won their match, and it was a simple wager. He got to pick something he wanted. And if it sounded good to Keith too, well, that was a pleasant coincidence..."The One with the Bubble Bath".





	Fluid Dynamics

“Shiro…” Keith panted out as he gave up on trying to keep his trembling arms straight. He pitched forward onto his elbows, the sudden movement sloshing the water in the tub and sending the heaps of bubbles into motion over the heated pool. Steam filled the small room, making it hard to breath –or think– especially not when he was feeling this good. 

“You know that winning a bet usually means you chose something for _yourself,_ right?” Keith continued, gritting his teeth as another unpredictable cluster of vibrations hit. His knees slipped outwards in an unconscious plea, his thighs holding him upright only when the outside of his legs pressed tightly against the sides of the Altean tub. 

“Oh, this is for me,” Shiro teased back. 

Keith moaned, dropping his head until the tickle of bubbles against his skin made him stretch upwards again. “Debatable…” he mumbled, relaxing slightly as the vibrating plug let off for a moment. He tried to push himself back up and nearly melted again as Shiro’s hands stroked over his tired, trembling muscles, still determinedly avoiding the heavy ache between Keith’s legs.

And Keith knew that this slow teasing was what Shiro wanted, but that didn’t keep a part of him from feeling slightly selfish. No matter how hard it was not to demand Shiro go faster. No matter how hard it was not to touch himself. No matter how hard it was to not touch Shiro…

“I love the way you look like this,” Shiro whispered, breaking into Keith’s distracted thoughts. He was kneeling so close behind Keith, massaging soothing circles over Keith’s upper thighs. And as if Shiro’s voice or touch alone weren’t enough to flood Keith with lazy pleasure, whatever random pattern that had been programmed into the plug chose that moment to whir back into life, the initial teasing pulses driving upwards into a heavy rattle. 

Keith’s next words dissolved into a thready moan as his head dropped steadily down towards the film of scented bubbles. Shiro laughed and caressed up Keith’s body, hands gentle as he threaded steady fingers through a handful of Keith’s dark hair. 

With a sigh Keith sank forward, trusting Shiro to keep him from going face-first into the water. As he let Shiro take more of of his weight, the pain anchored him to the moment, blending in easily. The sharp edge pushed the pleasurable sensations even higher. 

When the vibrations from the plug stilled, Keith gathered himself back up onto unsteady hands and knees and Shiro gently released his hair, stroking the remnants of pain away. 

Keith felt his chest shudder with his quiet, unsteady breaths as he tried to wait motionless. _Whatever Shiro wants to do,_ he reminded himself. Shiro’s hands didn’t leave him for more than a moment though. Their touches were silk and metal against his thighs, warm from the bath itself. The skin of Keith’s thighs was almost too sensitive and he pushed himself back at Shiro with a wordless plea. 

Keith’s momentary silence was shattered as the plug started up again, heavy and pulsing. Teasing. He’d been teased for so long. It was too much. It wasn’t nearly enough. He couldn’t decide and his thoughts fractured into quiet, needy moans that slipped free as the vibrations peaked. “Ah… ah… ng...” He stretched his body upwards, shifting his balance carefully so that he could unsteadily reach back for Shiro. 

“No touching,” Shiro’s voice was quiet and commanding. With a frustrated noise, Keith collapsed, dropping his hand to the side of the tub as if holding onto the edge could substitute for holding onto some remnant of mental clarity. Shiro’s hands travelled up to where the plug met Keith’s body, tracing hot, wet lines across his sensitized skin. “Fuck,” Shiro whispered. “You’re so tight around this.”

Keith lived for the moments when Shiro’s voice melted into something that soft. He held his breath as Shiro lightly pressed over the toy. 

Keith clenched around it relentlessly with the vibrations; trying to focus on Shiro’s touch through the mechanical distraction. There wasn’t enough of a pattern for him to anticipate. Involuntary tightening spread up through his abs, down through his splaying legs. It was tantalizingly, almost enough to make him come. But not quite. The need to have just that little bit more, even just a touch of direct stimulation was maddening. 

Another heavy vibration shot another wave of contractions through him, and his hands spasmed helplessly into fists. “Shiro,” he pleaded weakly, needing to rest his head somewhere. “Ah-” he squirmed as this time the vibration continued for longer. He could feel a sense of stretch return as bearing down on the source of the teasing pleasure almost forced it out. 

Shiro definitely noticed. He laughed softly. “Mmm. _Fuck._ You’re so tight, babe, how long has it been?” Keith moaned as he felt Shiro push the thickest part of the plug back into his body. 

“I can fit you,” Keith panted out, half a challenge and half a reminder, but the over-the-shoulder glare he intended to shoot at Shiro ruined by the way his flushed face went slack and his teeth found the flesh of his own lip as the vibrations pulsed away inside him. 

He gave up on holding his head up. At the edges of his vision he could see bubbles starting to cling to the ends of his hair; an obvious sign of how often he was starting to fail at holding himself above the water. His hips nudged backwards at Shiro’s hands. “Please,” he relented, finally driven to beg. A soft, ragged whisper might have been all he could manage but it was apparently enough. 

Shiro pulled Keith’s hips back and he could feel the heat from Shiro’s own arousal glide teasingly over the cleft of his ass as Shiro shifted against him. Keith bit at his lip, shoulder blades pulling together as he waited, expecting more. Even in the water Shiro’s body was hot against him, or maybe it was purely the sensation of Shiro’s calves between his own, the promise of what was to come, that sent flames licking along his nerves. But even as he braced, his mind whirred - Shiro’s movements were tentative, exploratory. 

“Alright…” Shiro finally came to a decision. _It was too slippery,_ Keith finally made the connection as the shifting movements behind him caused his knee to skid forward along the bottom of the pool. Keith spared a faint moment of regret, and then his brain power tried to refocus on _not falling_ when all his attention wanted to be on something else. But Shiro’s hands pulled Keith firmly up against him, pinning Keith’s back to his chest. Slowly, choreographing his intentions with touch, Shiro stood up, and Keith shakily followed his lead. 

There was a brief moment of fear that his legs wouldn’t hold him, not after being teased for so long, but Shiro’s arms never left him. Keith didn’t resist when Shiro guided him lazily down over the towels they’d left spread around the sunken bath. 

He let himself sprawl backwards. Lost to his own desires, Keith gripped onto Shiro’s wet body, pulling Shiro down overtop of him. Keith stared up at him, drinking in the sight. The sudden intimacy of meeting Shiro’s gaze like this sent a crackling layer of energy surging around Keith’s heart, and his small smile was instant and irrepressible. He was always left half in awe when Shiro’s eyes were this smoky-dark, this focused on him. But then Shiro’s lips were on Keith’s neck and Keith’s eyes slammed shut as Shiro kissed hot trails over his wet skin. 

Keith pressed himself up into Shiro’s body, grinding, holding onto Shiro’s shoulders as if they were a lifeline. His mouth fell open in a silent prayer at the bliss of being able to press into Shiro after being untouched for so long. His hips thrust forward in tiny circles, as slow as Shiro’s tongue against his body, trying not to go _too fast_ , trying not to do anything to make Shiro pull away or scold him. Not when he’d been teased for this long. He couldn’t hold on for much longer. 

Shiro shifted up over him, their chests sliding together as he reached for something off to the side. The clicking sound signalled that he had found the bottle of lube before wet skin began to catch uncomfortably on wet skin. 

He paused. “How do you want this?” Shiro asked, his voice rough. 

But Keith was unable to answer immediately. Keith’s eyebrows had twitched together and his body arched upwards and froze in a tense bow, the small undulations of his hips the only movement as he silently rode out another set of vibrating pulses. _He definitely wanted to be fucked._

“Mm….” he managed when he could open his eyes, sinking back into the towels. Each word seemed to catch in gritted teeth as the rising and falling hum of the vibrator became more constant. “You won that damned match,” he reminded Shiro, voice thick with lust. “So your choice…” He hooked one of his legs around Shiro’s, keeping the other pinned against him. He felt wrecked already, spread out below Shiro, both of them flushed from the heat of the room and the endless teasing. 

Keith’s fingers traced lower, squeezed into Shiro’s hips, as if he could physically anchor them together with his grip. 

“Oh,” Shiro said softly, freezing when Keith did at another round of buzzling. “That’s….” he trailed off, eyes closing in bliss. 

Strong? Good? Whatever word Shiro wanted to fill in there Keith would agree. “Yeah,” Keith managed between hitched breaths. 

For a moment Shiro just let himself rest against Keith’s body, hand pressing down on Keith’s rigid abs as the faint vibrations travelled, almost tickling. His heavy cock skimmed alongside Keith’s, both of them so hard.

When the plug let up Shiro pulled himself back, breaking Keith’s weakened grip. There was a moment where Keith made a keening noise of protest, but then Shiro was smoothing lube over them both with determined strokes. “Shiro..” Keith gasped out, knees raising to bracket his lover. 

“Enough teasing?” Shiro asked. 

“More than…” Keith let his teeth latch onto his lip to keep from adding a command to his reply. Instead he let his knees fall apart, sprawling open and wanton for Shiro. 

Shiro leaned over and kissed him fiercely, lips and tongue in near-constant motion as he brought himself up to kneel between Keith’s legs. 

When Shiro leaned back, Keith tracked him with lazy, half-lidded eyes. Shiro let his hands trail down Keith’s body, drawing silvery trails over Keith’s water-beaded skin. His fingers caught on Keith hipbones, and he gripped them, hard, pulling Keith’s hips up off the floor, slung over Shiro’s thigh’s. With a precious look of concentration, Keith distractedly watched Shiro’s hand smooth over his own cock, fascinated by the way the metallic fingers twisted and gripped, the contrast beautiful.

Shiro paused. 

Keith shuddered. What he wanted to do was to beg for Shiro to go faster. To just fuck him already. But he was pretty sure that was against Shiro’s intention for their evening, although Keith was probably was taking that more seriously than Shiro was at this point. But if Shiro didn’t _move_ , didn’t hurry up, Keith was going to go insane. “Please Shiro,” Keith pleaded in frustration, trying to keep his tone from slipping into demands, not now when Shiro’s cock was close enough that he could feel the heat against him. 

But it was Shiro, and Keith always wanted to be closer. _Always._

Keith watched with longing as Shiro’s slick hands left his cock, watching as it bobbed back up to hit Shiro’s abs. The visual weight of it made his mouth water. Shiro’s hands were distracting as they smoothed over Keith’s thighs. The steamy room around them was at odds with the shivers that followed Shiro’s delicate traces over the sensitive skin of his inner thighs. 

Keith’s toes curled hard as Shiro took hold of the flat base of the plug, holding his breath as he arched upwards again, closing his eyes to better focus on the feel of it. He tried to relax as Shiro’s thumb turned it off, pulled it free and set it aside. 

He told himself that it was just because Shiro had won that silly wager that Keith held himself still when Shiro lifted his hips. Not because of the thrill he got from the way that Shiro almost stopped breathing at the sight of him like this. Not because it turned him on so much to be vulnerable and under Shiro’s control. His cock twitched against his belly, excitement driven now entirely by his thoughts, his anticipation.

Shiro’s thumbs dug into his flesh, spreading him further apart. Keith threw his head back, uncomfortable at the intimate attention, heart racing and palms sweating and so unbelievably hard. 

One of Shiro’s hands left him, and the loss of contact made Keith look back up. He licked his lip, unsure of what to expect. 

Playfully, Shiro’s palm pushed his cock down, and he shifted them both far too easily. He looked down and met Keith’s eyes, licking his lip once. “You look so amazing all spread out for me like this…” 

Keith had to break the eye contact, it was too much, far too much intimate between the praise and his position. He turned his head to the side, trying to concentrate on the texture of the towel beneath his sheet rather than the way he was so vulnerable to Shiro, so helpless in the face of praise and lust and not being able to control the situation like he usually did. 

“You’re all blushes; so shy when you’re not in control…” Shiro didn’t stop. Someone needed to stop that mouth, Keith decided, cracking open an eye to half glare as he brought his foot around to nudge Shiro’s back impatiently. “… but you love when I have you all spread out over my lap…” 

Keith couldn’t disagree, but he refused to admit it. He narrowed his eyes, shifting the focus back to Shiro. “You enjoy watching me.” 

“Almost as much as you’re going to enjoy this…” Shiro promised with a cheeky smile that shouldn’t have been so endearing. And finally, _finally_ , pushed forward.

Keith’s hands fisted in the towels. There was still that damn instinct to tense up. His heartbeat tattooed a quick rhythm into his head as he willed himself to relax. Let himself soften to let Shiro in. Shiro rocked gently forward, his hips pressing in longer thrusts as he moved slowly, letting Keith get used to his girth.

His body melted down into the towels, the tension dissipating as he was finally filled. “Ooooh…..” Keith’s appreciative tone was soft, barely even a vibration of sound over his long exhale. But it was pure bliss. 

Keith ran his hands up his own body, playing over his damp skin, distracting himself as Shiro started to move. 

With a sort of challenging gaze at Shiro he reached for himself, wrapping a familiar fist around his own length and stroking. He smirked as he got away with it, looking up at Shiro’s face. Shiro’s eyebrows crinkled together slightly and eyes half fluttered shut, lost to his own world of sensations. 

Keith let his own eyes soften as he concentrated more on the feel of Shiro inside him, his own strokes still quicker that Shiro’s slow thrusts. The angle was amazing. Each curl of Shiro’s hips resulted in a long drag of pleasure, hitting spots the damned plug had only barely grazed. 

He was lost to it for a moment; no words needed between them. He felt Shiro’s hands on his legs, and followed the gentle encouraging touches, letting Shiro rearrange them how he wanted. Shiros fingers closed around his ankle, and Keith wasn’t sure how much more he could sprawl open, but Shiro lifted Keith’s leg, bracing his calf against his shoulder. 

“That ok?” Shiro asked, lips kissing the words into the fine hair on Keith’s leg. 

Keith let out another blissed out moan, one hand tangling in his own hair, hiding his face, as his other hand moved faster over his cock. “God yes,” he hissed, letting Shiro practically split him apart. He could brace slightly against Shiro, move a little. He was just flexible enough.

Shiro kept up his pace, relentless and slow. “Shiro…?” Keith’s hand stopped stroking, gripping tightly at the base of his own cock as he paused, feeling himself flinch around Shiro’s continued movements. He was so close. Too close already. 

“Don't stop, baby,” Shiro groaned out. “Make yourself come for me.”

Keith whimpered and started stroking again, half distracted as Shiro gripped his other ankle, effortlessly moving it to his other shoulder. Keith’s breathing hitched as Shiro leaned forward, practically bending him in half.

Keith gasped, too close to his own climax to last long with this shift in position, with Shiro’s determined words. Each of Shiro’s thrusts felt deep enough to push even the air from his lungs. It felt so deep this way. He felt the rising tension in his gut, 

“Shiro,” Keith tried to stutter out a warning, but then Shiro’s lips were against his, rough and demanding. Shiro’s tongue lapped into his mouth, hot and wet, and Keith’s hand stilled. A tremble spread out through his legs that had nothing to do with the position he was pinned in. 

He bit off a cry as he spilled between them, let Shiro kiss away his moans with hungry lips. He kept his eyes tightly shut. Keith's heart felt like it was going to escape his chest.Ship’s kisses turned tender, reassuring as he eased Keith through the orgasm. 

Shiro started moving again, this time with more of a sense of urgency. Faster. Deeper. Keith squirmed, and Shiro relentlessly pinned him in place. No escape. Keith caught his breath, caught his lip with his teeth and watched Shiro move above him. 

There was a slight hesitation at the peak of his strokes in response to Keith coming apart around him. Just enough to slightly alter his smooth pacing Keith jerked one leg free from Shiro’s shoulder, sprawling more comfortably beneath him. He reached up, brushed a hand through Shiro’s hair with trembling fingers. Shiro closed his eyes and leaned into the touch. 

Keith pulled his other hand from between them, stroking up through the mess he'd coated his own stomach in. 

With a calculated look he reached up with his slick hand, tracing a careful, wet line over Shiro’s velvety lower lip. Shiro’s eyes cracked back open. His hips snapped unsteadily, and a surge of triumph flooded through Keith. Keith's other hand fisted into Shiro's undercut, and when Shiro’s hips stilled for a moment, he pushed two fingers into Shiro's mouth. He bent them inwards, stroking down over Shiro’s tongue. He felt the moan a moment before the noise actually registered, and his lips curled in satisfaction. Shiro's lips were soft but demanding as they sealed around his fingers, the insistent suction heady enough to make Keith's dick briefly jump back to life. 

Shiro closed his eyes again, tongue playing in the space between Keith's fingers as Keith played, splitting them and moving gently against Shiro’s mouth. 

On Keith’s legs, Shiro’s own fingers curled into vices. Keith could practically watch him surge towards his own end, breathing getting erratic, hips moving more with the pace Keith’s fingers set than with his previous steady tempo. 

It only took a few more moments before Shiro pushed forward heavily, gathering Keith in close to him. His body stilled with a muffled groan at the rush of finding his own release. Shiro stayed locked in position for a moment, frozen with the pleasure as Keith carefully reclaimed his hands. Shiro’s head fell forward and he gasped against Keith’s neck, breath hot and wet where he nuzzled in. “Keith,” he whispered the name like it was a lifeline, “Keith.”

Keith felt the moment of Shiro’s chest as he drew in a deep, shudder breath. Shiro’s hands smoothed soothingly over where he’d been gripping. He brought their foreheads together with a quiet sigh. After a moment Shiro pushed himself back, pulling out and rolling over in a sleepy stretch. 

The emptiness was always vaguely unpleasant. Keith lay there for a moment letting the soft sounds of water from the pool and the cadence of Shiro’s tired breathing soothe over him. It was only another heartbeat or two before he felt too far away. He nudged his body over so that he was flush against Shiro’s side and turned, draping himself firmly over Shiro in a demand for more contact.

Shiro shifted Keith into his arms, cradling him against a rapid heartbeat and still-recovering breaths. Keith let him, blissed out. The heavy heat of the room around them made his head light and body boneless. He let his head fall limply onto Shiro’s shoulder as Shiro shifted them both over, and then settled into the still-warm bath again. 

“I could get used to this…” Shiro murmured sleepily, letting his own head fall back against a rolled up towel. 

“Mmm….” Keith replied, half-asleep already, letting his hands run lazily over Shiro’s chest in a partial effort to help clean them both. 

“Next bet…” Shiro mused, entirely too focused on an abstract idea for Keith’s liking, “the next time I win I’m going to–”

Keith’s competitiveness flared, adding an edge to his fond tone. “Next time you won’t win.”

“Maybe.” Shiro agreed, too easily, in a way that made Keith bristle at the smug knowledge behind it. A part of him hated that Shiro’s confidence probably wasn't misplaced. 

Still, a larger part of him eagerly looked forward to losing their next wager. 

-Fin-


End file.
